The present invention relates to a method and a system for quickly measuring absorbancy in, for example, an automatic biochemical analyzer.
FIGS. 1 and 2 show a conventional apparatus used in various biochemical analyses of liquid samples, such as serums.
In FIG. 1, a plurality of reaction tubes 1a to 1l are arranged in ring-shaped constant-temperature bath 2, which is located on a rotating table (not shown), thus constituting a reaction line. Tubes 1a to 11, which are made of glass or plastic, and which are optically transparent, rotate at regular cycles in the direction of arrow y of FIG. 1. Although in this description, the reaction tubes are only twelve in number, the number of reaction tubes used in an actual apparatus are several times as many as those illustrated. A washing unit, sample dispensing unit, reagent dispensing unit, mixing unit, etc., (not shown) are arranged in predetermined positions around bath 2, corresponding to the individual reaction tubes. In positions A, B, C and D, the reaction tubes are subjected to specific operations. In the states shown in FIGS. 1 and 2, tubes are at a stop. In position A, as shown in FIG. 1, reaction tubes 1b, 1c and 1d are washed. Thus, samples and reagents, dispensed to and mixed in the reaction tubes before reaching position A, are washed away in position A. Likewise, in position B, another sample is dispensed afresh to the reaction tube la washed in position A. A reagent is dispensed to the reaction tube 1l in position C, and a mixture of a sample and the reagent in the reaction tube 1k is performed in position D. A photometric section, which includes the light source, for example, lamp 3 and photodetector 4, is arranged at right angles to the course of rotation of the constant-temperature bath 2 in the direction of arrow y. Thus, optical axis 5 between lamp 3 and photodetector 4 crosses the course of rotation. The quantity of light passing through the tubes varies, due to the states of the liquid mixture. When the reaction tubes intercept optical axis 5, therefore, photodetector 4 obtains absorbancy measurement data in accordance with the degree of transmission.
After the state of FIG. 1 is maintained for a predetermined period of time, ring-shaped constant-temperature bath 2 is rotated in the direction of arrow y for another predetermined period of time. After the individual reaction tubes are moved, the bath 2 is stopped again. This rotation causes each reaction tube to move for a distance equivalent to one revolution plus one pitch.
FIG. 2 shows the arrangement of reaction tubes 1a to 1 in a position reached after such movement of the tubes from the position of FIG. 1. Also in this state, the individual operations are performed in positions A to D.
One cycle is defined as a combination of each rotation time and each stopping time. As such cycles are repeated thereafter, the reaction tubes advance pitch by pitch. Thus, each reaction tube can perform a continuous absorbancy measurement. If twelve cycles of operation are repeated, for example, twelve absorbancy data can be obtained for each reaction tube.
Such an apparatus, however, requires rotation time for absorbancy measurement and stoppage time for the washing, dispensing, and mixing processes. Thus, absorbancy measurement cannot be easily performed at high speed.
Thus, there is a demand for the development of a method for high-speed measurement of absorbancy.